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New methods of agricultural production must be utilized if the additionaltwo billion people expected to populate the world over the next 30 years are to befed. And, this must be done in the face of the world's natural resource basebecoming increasingly fragile (FAO, 2003: 3). Technologies are becomingavailable to further increase food production and conserve our natural resources,continuing the advances made in this field during the past century.One of the advances made during the past century was the invention ofsynthetic nitrogen fertilizer. At the time of this important discovery, Europeansand North Americans were mining guano and nitrates around the world toprovide nutrients for their agriculture and food production. These resources ofnitrogen were becoming exhausted and increasingly scarce (DeGregori, 2002:139). They needed to add nitrogen to replenish their fallow fields and syntheticnitrogen was the answer. “One might not call the Haber-Bosch synthesis ofnitrogen fertilizer the greatest invention of the twentieth century as Valclav Smilhas done, but it would be difficult to argue against him, as we simply could nothave fed even half the worlds population today without it” (DeGregori, 2004:128). The technologies of the past enabled us to produce higher-yielding seedsand gave us the inputs required to make them grow and just as technology savedthe population of today from massive food shortages; it will undoubtedly play amajor role in helping the people of tomorrow (FAO, 2003: 3).1It would be nice to have an increase in agricultural production --enough tofeed a yet to be world of 9 billion humans-- without an environmental cost, butthat is simply not possible. It is possible, however, to reduce the environmentalcost of increasing agricultural production (DeGregori, 2002: 145, 166).DeGregori goes on to contend that, “Without a continuing flow of new technology,forest and wildlife preserves could be lost to agricultural expansion with the everincreasing possibility of species extinction and consequent loss of biodiversity”(2004: 129). In fact, new transgenic biotechnology can provide various foodcrops that have the potential to increase yields by decreasing the damagecaused by pest infestations, while reducing chemical usage. The reducedchemical usage by farmers can reduce environmental damage caused byagriculture production. Not only do these transgenic crops have the potential toreduced environmental damage they also have the potential of growing despiteabiotic stresses (e.g. aluminum, salt, and drought), all the while providing morenutrition to consumers (FAO, 2003: 72,). Considering where technology hastaken us and where we are headed, it is logical to assume that “plantbiotechnology is not simply a luxury but increasingly a necessity” (DeGregori,2004: 130). Transgenic technology is a tool that has the potential to ease ourfuture woes.Genetic modification of food is often a misunderstood phrase. Almostevery crop we use as a source of food has undergone some type of geneticmodification. Our ancestors searched for crop plants, utilizing the ones thatsurvived insect infestation. By using and planting the seeds, they unknowingly2were selecting crops with better resistance to pest. By cross breeding theirselections, humans modified crops to be more productive and heartier as well asfor specific features such as faster growth, larger seeds, and sweeter fruits. It isunderstood that “Farmers and pastoralists have manipulated the genetic make-up of plants and animals since agriculture began more than 10,000 years ago.Farmers managed the process of domestication over millennia, through manycycles of selection of the best-adapted individuals. This exploitation of the naturalvariation in biological organisms has given us the crops, plantation trees, farmanimals and farmed fish of today, which often differ radically from their earlyancestors” (FAO, 2003: 9).The first major insight into the science of breeding plants was in 1865when Gregor Mendel, the father of genetics, explained how dominant orrecessive alleles could produce the traits we see and that these traits could bepassed to offspring. Plant breeding advanced in the wake of Mendel's discovery.Breeders introduced their new comprehension of genetics to the establishedmethods of self-pollinating and cross-pollinating plants. It was not long beforeplant breeders discovered that, during the natural evolution of plants,spontaneous mutations would occur. Some of these mutations produceddesirable and sought after traits. However, the natural rate of spontaneousmutation was unreliable not to mention very slow (CSU, 2004: A).Researchers and plant breeders wanted to find a way to tap into thisprocess. Their goal was to induce mutations so they could quickly create bettervarieties of food. As science progressed from the late 1920’s into the 1970’s,3researchers were genetically modifying foods with induced mutations (CSU,2004: A). They induced mutations by exposing plant parts with chemical orphysical mutagens effectively mimicking spontaneous mutations (FAO, 2003:10). Some of this mutation breeding involved “deliberately bombarding plants ortheir seeds with radiation with the intention of creating mutations” (DeGregori,2002: 126). With out mutations, there would be no rice, or maize or any othercrops, as we know them (FOA, 2003: 10). In fact, over two thousand twohundred varieties of mutant crops have been officially released to date; all ofthem beneficial and without the slightest evidence of harm (DeGregori, 2002:127).Despite the successfulness of genetic modification by the conventionalbreeding techniques discussed so far, many generations of breeding are neededto isolate the desirable traits and minimize the undesirable traits. Through theresearch of the 80’s and 90’s we know that “biotechnology can make theapplication of conventional breeding methods more efficient” (FAO, 2003: 9).With biotechnology, we can transfer desired traits into plants faster and moreselectively by transplanting the specific desired gene into the crop plant.As these biotechnology procedures developed, the terms geneticmodification, genetically engineered, genetically modified and transgenic havebecome interchangeable terms in today’s society. When most people speak ofgenetically modified foods, they are actually referring to transgenic foods. Wewill use those terms interchangeably through the rest of this paper. A transgeniccrop plant has a gene or genes artificially acquired as opposed to acquiring them4through pollination. The gene that has been successfully transferred by artificialinsertion is known as the transgene. The transgene can come from a differentspecies of plant or from an organism that is from a completely different kingdom(CSU, 2004: B). This is useful in situations “When the desired trait is found in anorganism that is not sexually compatible with the host, it may be transferredusing genetic engineering” (FOA, 2003: 15). Genetic modification is seen as amore precise extension of conventional approaches to modifying plants and “Atthe same time, genetic engineering can be seen as a dramatic departure fromconventional breeding because it gives scientists the power to move geneticmaterial between organisms that could not be bred through classical means”(FAO, 2003: 22).“Three distinctive types of genetically modified crops exist: (a) ‘distanttransfer’, in which genes are transferred between organisms of differentkingdoms (e.g. bacteria into plants); (b) ‘close transfer’, in which genes aretransferred from one species to another of the same kingdom (e.g. from oneplant to another); and (c) ‘tweaking’, in which genes already present in theorganism's genome are manipulated to change the level or pattern of expression.Once the gene has been transferred, the crop must be tested to ensure that thegene is expressed properly and is stable over several generations of breeding.This screening can usually be performed more efficiently than for conventionalcrosses because the nature of the gene is known, molecular methods areavailable to determine its localization in the genome and fewer genetic changesare involved” (FAO, 2003: 16).5“Neither of the major food grains – wheat and rice – currently havetransgenic varieties in commercial production anywhere in the world” (FAO,2003: 38). “The most widely grown transgenic crops are soybeans, maize,cotton and canola” (FAO, 2003: 38). Other types of transgenic crops that arebeing cultivated commercially include very small quantities of virus-resistantpapaya and squash, but most of the transgenic crops planted so far haveincorporated only a very limited number of genes aimed at conferring insectresistance and/or herbicide tolerance (FAO, 2003: 17).Bt-corn is one common example of a genetically modified crop that resistspest and is also less likely to be infested (30 to 40 times lower) with Fusarium earrot, a fungal infection that produces toxins, called fumonisins, which are oftenfatal to pigs and horses and can cause esophageal cancer in humans(DeGregori, 2002: 12). The Bt gene in Bt-corn is acquired from the Bacillusthuringiensis bacteria. Sprays and powders that are comprised of this Btbacterium have been, and continue to be, used regularly for pest management.When scientists create Bt-corn, they start by selecting a strain of corn for the Bttransformation that has agronomic qualities for yield, harvest ability and naturaldisease resistance. Next, they identify a strain of Bt that will destroy the choseninsect. The Bt gene that generates the pesticide protein is detached andconnected to another gene (the resistant gene) that has been isolated for itsresistance to a herbicide. The newly attached genes are inserted into the pre-selected corn plant cells. The scientists then locate the plant cells that containboth the Bt gene and its connected resistant gene. Not all of the plant cells will6have transformed in this way, so it is important for them to find those two genesstill attached to one another. The plant cells that meet the criteria are then grownin the presence of the herbicide. The cells that are not affected by the herbicideare taken and grown into whole plants, by a process called tissue culture. Thoseplants go on to produce a protein that is deadly to the targeted insects and cornbores. Successive generations will also inherit the insect resistant features(CSU, 2004: A, B, C, D).Specifically, “Bioengineered Bt (Bacillus thuringiensis) corn has a proteinthat is activated by enzymes in the insect gut when ingested by the corn bore orother insect pest. The activated Bt protein binds to specific receptor sites in thegut and inserts itself into the membrane of the insect gut. Bound to the innerlinings of the stomach, the Bt toxin causes a influx of water into cells that swelland destroy the insect digestive system (Nester et al. 2002). ‘As the gut liquiddiffuses between the cell, paralysis occurs, and bacterial invasion follows’(Benarde 2002, 117). This leads to insect starvation and eventual mortality andis the same mechanism used by the live Bacillus thuringiensis bacteria to kill theinsect and then feed and multiply on its remains” (DeGregori, 2004: 109).This Bt protein is not toxic to humans because it is broken down in thedigestive system. The stomachs of mammals are acidic, while those of insectsare alkaline. The Bt’s crystalline protein is alkaline, and consequentially thereceptor sites for this protein are lacking in an acidic environment, rendering theBt harmless to all but insects (DeGregori, 2004: 109).7By allowing the corn and other crops to produce their own pesticides andherbicides through genetic modification, we have shifted the traditional focus ofagriculture from one of trying to produce higher yields, to one that also includes alower environmental impact. “The scientific consensus is that the use oftransgenic insect-resistant Bt-crops is reducing the volume and frequency ofinsecticide use on maize, cotton and soybean” (ICSU, cited in FAO, 2003: 69).There are several positive effects resulting from reduced pesticide spraying. Oneis that field workers are protected from exposure to pesticide poisons. Anotherpositive result is that pesticide runoff into water supplies is reduced with areduction in pesticide application. In addition, less pesticide spraying causesless damage to non-target insects. “Reduced pesticide use suggests that Bt-crops would be generally beneficial to in-crop biodiversity in comparison withconventional crops that receive regular, broad-spectrum pesticide applications,although these benefits would be reduced if supplemental insecticideapplications were required” (GM Science Review Panel, cited in FAO, 2003: 69).The fact is, “Scientist agree that the use of conventional agriculturalpesticide and herbicide has damaged habitats for farmland birds, wild plants andinsects and has seriously reduced their numbers” (FAO, 2003: 68). Along withinsect resistant crops, it is speculated that herbicide tolerant crops have thepotential to promote biodiversity as well. If changes in herbicide use allow weedsto remain for longer periods of time it would provide habitat for birds and otherspecies. Herbicide tolerant crops also would enable the use of less toxic formsof herbicide and encourage the adoption of low till crops that result in benefits for8soil conservation by conserving soil that is more easily eroded when fields areconventionally cultivated (FAO, 2003: 69).Scientists concede that more studies are needed which compareconventional agricultural practices with the agricultural practices that utilizetransgenic crops (FAO, 2003: 68). Because large-scale cultivation of transgeniccrops is a newer technology, the effects of crop production on the environmentare still emerging. As with any type of agriculture, whether conventionally doneor not, there are adverse affects to the environment. The idea is to minimize theadverse affects while maximizing the benefits.Experts agree that changes in agricultural practices, such as herbicideand pesticide use, due to transgenic crops may have positive or negative indirectenvironmental effects depending on how and where they are used (FAO, 2003:66). However, it is currently acknowledged that, “Negative environmentalconsequences, although meriting continued monitoring, have not beendocumented in any setting where transgenic crops have been deployed to date”(FAO, 2003: 57).There is concern that long-term use of herbicide tolerant Bt-crops will leadto insects and weeds that are resistant to glyphosate and gluphosinate, theherbicides associated with these crops (FAO, 2003: 71). “Similar breakdownshave routinely occurred with conventional crops and pesticides and, although theprotection conferred by Bt genes appears to be particularly robust, there is noreason to assume that resistant pests will not develop” (GM Science ReviewPanel, cited in FAO, 2003: 71).9The expected development of resistant pest and weeds has led scientiststo advise that farmers implement a resistance management strategy when theyplant transgenic crops (FAO, 2003: 72). The proliferation of insects that canresist Bt technology would be considered an environmental set back because theuse of more toxic forms of chemical control would be needed to get rid of thepest.The U.S. Environmental Protection Agency, which regulates Bt-cropsbecause of their pesticidal classification, agrees with scientist recommendationsregarding the need for a resistance management strategy. The U.S.Environmental Protection Agency requires farmers who plant Bt-crops to includerefuges. An example of a refuge is a block of non-Bt-corn planted near a Bt-cornfield (EPA, 2004). “EPA requires all farmers who use Bt-crops to plant aportion of their crop with such a refuge. The aim of this strategy is to provide anample supply of insects that remain susceptible to the Bt toxin. The non-Bt refugewill greatly decrease the odds that a resistant insect can emerge from a Bt fieldand choose another resistant insect as a mate. The likelihood that two insectswith a resistant gene will find each other and mate is greatly decreased” (EPA,2004).It is debatable how effective this system can be, considering it isdependent on farmers complying with the requirements to plant enough refuges.The data collected by the Department of Agriculture’s National AgriculturalStatistics Service, showed that nineteen percent of all Bt-corn farmers in Iowa,Minnesota, and Nebraska, roughly 10,000 farms, violated the Environmental10Protection Agency’s refuge requirements in 2002. Thirteen percent of farmersgrowing Bt-corn planted no refuges at all. Although most farmers that grow Bt-crops plant enough refuges, those that do not need to meet their obligations sothat the benefits of this agricultural biotechnology will not be squandered (CSPI,2003).There are issues concerning the coexistence of non-transgenic crops(organic and conventional) and transgenic crops. Transgenic crop farmers thatuse Bt-crops and do not comply with resistance management strategies increasethe possibility those insects will develop immunity to Bt. The Bt soil bacterium issometimes used by non-genetically modified crop farmers to protect their cropsfrom insect infestations, and Bt resistant insects will cause these farmers to loseBt spray as an effective deterrent (Cummins, 2004).In addition, some people want to avoid eating foods that containtransgenes, even though genetically modified crops are as safe to eat as theirnon-genetically engineered counterparts are. Most people would agree that weshould not “interfere with the rights of others” (DeGregori, 2004: 61). However,people might not be able to avoid transgenic crops because wind, birds and otherpollinators can carry genetically altered pollen into non-genetically modified cropfields, resulting in a hybridized seed that will contain genetically modified DNA(Cummins, 2004).This gene flow from genetically modified crops could make non-transgenic farming very difficult. Currently, “Management and genetic methodsare being developed to minimize the possibility of gene flow” (FAO, 2003: 67).11Artemio Salazar suggest that one possible way to avoid cross pollination is byemploying temporal isolation by planting Bt-crops 25 days before or after thenon-Bt-crops are planted (Pabico, 2003). “This is the same method used toavoid cross-pollination between white and yellow corn varieties” (Pabico, 2003).Another possible way to slow the gene flow of genetically modified pollen is toplant a buffer zone of trees around the field and have the different crops isolatedby an appropriate distance (CBC, 2002). One of the most promisingdevelopments is that “Genetic engineering can be used to alter flowering periodsto prevent cross-pollination or to ensure that the transgenes are not incorporatedin pollen and developing sterile transgenic varieties” (ICSU and Nuffield Councilcited in FAO, 2003: 67).The safety of genetically modified food to human health has always beena concern. “The main food safety concerns associated with transgenic productsand foods derived from them relate to the possibility of increased allergens,toxins or other harmful compounds; horizontal gene transfer particularly ofantibiotic-resistant genes; and other unintended effects. Many of these concernsalso apply to crop varieties developed using conventional breeding methods andgrown under traditional farming practices” (FAO, 2003: 59).The allergens and toxins can be controlled more effectively in geneticallymodified foods because the uses of genes from known allergenic sources arediscouraged and the genetically modified foods are rigorously tested for suchsubstances. Traditionally developed foods are not generally tested for thesesubstances even though they often occur naturally (FAO, 2003: 60).12The transfer of antibiotic-resistant genes has been addressed. Many hadbeen concerned about antibiotic resistant bacteria being transferred fromgenetically modified food to humans. This concern arose from the early dayswhen genetically modified crops were created using antibiotic-resistant markergenes. The possibility existed for those genes to pass from the food product intothe cells of humans. Therefore, development of antibiotic-resistant strains ofbacteria could have resulted (FAO, 2003: 60). In response, “researchers havedeveloped methods to eliminate antibiotic-resistant markers from geneticallyengineered plants” (FAO, 2003: 60).To ease safety concerns, genetically modified foods should becontinuously evaluated for safety. Any new transgenic creations need to beassessed with caution even though “the best scientific testing can find noevidence of harm and nothing in our current scientific knowledge gives us anyreason to expect to find harm by continued testing” (DeGregori, 2004: 83).There is potential for harm in organic or conventional plant breeding and there isno evidence genetically modified foods are less safe. The genetically modifiedfoods might even be safer than conventional crops when you consider that “Withtransgenic, conventional farmers will be able to produce a crop as close to beingtruly pesticide-free (the only pesticide possibly being a gene that expresses aprotein toxic only to specific pest) as has ever been done by humans”(DeGregori, 2004: 90).DeGregori asserts that with crop protection built into transgenic cropsthere will be little question as to which crop, conventional or organic, has the13fewest toxins, either applied by the farmer or produced by the plant (2004: 90).It is worth noting that “Although the international scientific community hasdetermined that foods derived from the transgenic crops currently on the marketare safe to eat, it also acknowledges that some of the emerging transformationsinvolving multiple transgenic may require additional food-safety risk-analysisprocedures” (FAO, 2003: 4).The future holds other possibilities for transgenic foods besides justincorporating genes aimed at insect resistance and/or herbicide tolerance.“Modern biotechnology has the potential for bringing previously degraded landsback into cultivation with, for example, salt tolerant plants that could be cultivatedon lands salinated by centuries of irrigation. This would also relieve or reducepressure to bring other lands under cultivation” (DeGregori, 2002: 141). Similarworks in progress are to improve the tolerance of plants to other environmentalstresses such as temperature extremes. Scientist are developing wheat withimproved tolerance to aluminum because thirty percent of all arable land is notsuitable for plant growth due to aluminum in acid soils (FAO, 2003: 9, 16). Inaddition, “Biotechnologists are working to create even more efficient plants,including the use of water” (DeGregori, 2004: 134). There is even the possibilityof creating crops that have nutritional enhancement. For instance, with rice weare “fast approaching a theoretical limit set by the crop’s efficiency in harvestingsunlight and using its energy to make carbohydrates” (Surridge 2002, 576 citedin DeGregori, 2004: 130). “Improving the photosynthetic efficiency of rice hasthe potential of increasing nutritional value and enhancing its ability to withstand14environmental stress” (DeGregori, 2004: 131). “The well-known transgenicGolden Rice contains three foreign genes - two from the daffodil and one from abacterium - that produce provitamin A. Scientists are well on their way todeveloping transgenic ‘nutritionally optimized’ rice that would contain genesproducing provitamin A, iron and more protein. Other nutritionally enhancedfoods are under development, such as oils with reduced levels of undesirablefatty acids. In addition, foods that are commonly allergenic (shrimp, peanuts,soybean, rice, etc.) are being modified to contain lower levels of allergeniccompounds” (FAO, 2003: 17).Public attitudes on transgenic food are as diversified and complex as theindividuals that make up society. “It is apparent that few people express eithercomplete support for or complete opposition to biotechnology” (FAO, 2003: 84).Studies show that attitudes are related to income levels.Although there are exceptions, wealthy counties have more views that arenegative with regard to genetically modified food than those of poorer countries.“In general, people in higher income countries tend to be more skeptical of thebenefits of biotechnology and more concerned about the potential risk” (FAO,2003: 77). Public support for genetically modified food differs widely whenconsidering the application of such technology. For instance, applications thataddress health and environmental concerns where looked upon more favorablythan applications promoting an increase in agricultural production (FAO, 2003:78).15Most people know very little about transgenic foods. The public’s mainsource of information on the subject is through news media like television ornewspaper. This lays great responsibility on companies that run theseinformation sources to get accurate information out to the public. Unfortunately,these media outlets are prone to report studies that result in negative findingsregarding genetic modification technologies.Even when those same studies are peer reviewed and found to beinaccurate, there is usually no follow up to report the facts. The result is amisinformed public.A good example of this would be the monarch butterfly controversy. In1999, a Cornell University entomologist named John Losey published a researchpaper, in the scientific journal Nature, claiming monarch butterfly larvae died aftereating milkweed leaves dusted with Bt-corn pollen. The paper immediatelyignited a worldwide controversy and led to intense news coverage that promotedthe supposed dangers of agricultural biotechnology. The New York Times evenran a front-page story on the topic (FAO, 2003: 71).Contrary to much publicity and street theater, the monarch butterfly isunharmed by ingesting the Bt protein at levels in which it is naturally exposed toin the wild (DeGregori, 2004: 117). Six independent teams of researchersconducted follow-up studies that discredited Loseys findings and showed that Bt-corn posed less risk to monarch butterfly larvae than conventional pesticides(FAO, 2003: 71).16None of the TV or newspaper media, excluding The New York Times, didfollow up reporting. The New York Times obscured their follow up story in theback pages. These types of irresponsible media coverage (or lack of coverage)have contributed to public confusion. “Many scientists are frustrated by the waythe monarch butterfly controversy and other issues related to biotechnology werehandled in the press. Although the original monarch butterfly study receivedworldwide media attention, the follow up studies that refuted it did not receive thesame amount of coverage. As a result, many people are not aware that Bt maizeposes very little risk to monarch butterflies” (Pew Initiative, 2002 cited in FAO,2003: 71).People forget that several US governmental agencies and numerousothers in the scientific community have tested the transgenic crops that arecommercially grown and all of them have concluded that transgenic crops are assafe (or safer) than their conventional counterparts. The evolution of geneticmodification in plant breeding has the potential to increase yields whiledecreasing pest infestations, reduce chemical use, relieve stresses such asaluminum, salt, and drought and make foods more nutritious.There will actually be no reasonable alternative to the use of newtechnology to feed the world's population three decades from now, which will begreater than it is today by more than two billion individuals. Despite thecapabilities of technology, there will be resistance to the production of foods thatcontain transgenes. Ironically, most of the resistance will be from wealthiercountries where the advances in technology most often occur. Promoters of17foods that contain transgenes will face opposition in two ways. One is throughrestrictions placed on their work by government, thereby delaying progress andincreasing costs. The other is through misinformation spread by those opposingfoods with transgenes. The spreading of misinformation will cause people torefuse to buy food that contains transgenes. In either case, the best way topromote foods that contain transgenes will be to emphasize the benefits to healthand the environment, not increased yields brought on by the production oftransgenic agricultural products.